1. Field of the Invention
The present invention relates to a method of modification of authorization details for a biometrics authentication device, a biometrics authentication method, and a biometrics authentication device, to perform individual authentication using characteristics of a portion of a human body. In particular, the present invention relates to a method of modification of authorization details for a biometrics authentication device, a biometrics authentication method, and a biometrics authentication device, to permit individual authentication using biometrics information of an authorized agent other than the principal.
2. Description of the Related Art
There are numerous portions of the human body which can be used to differentiate the individual, such as fingerprints and toeprints, the retinas of the eyes, facial features, and blood vessels. With advances in biometrics technology in recent years, various devices have been provided which identify biometrics features of a portion of the human body to authenticate individuals.
For example, because blood vessels and prints of the palms and fingers of the hands provide a comparatively large quantity of individual characteristic data, they are suitable with respect to reliability of individual authentication. Blood vessel (vein) patterns in particular remain unchanged throughout life from infancy and are regarded as being completely unique, and so are well-suited to individual authentication. Of this, individual authentication technology based on blood vessel images in the palm of the hand is explained.
First, at the time of registration or of authentication, the user brings his palm into proximity with an image capture device. The image capture device emits near-infrared rays, which are incident on the palm of the hand. The image capture device uses a sensor to capture near-infrared rays rebounding from the palm of the hand. Hemoglobin in the red corpuscles flowing in the veins has lost oxygen. This hemoglobin (reduced hemoglobin) absorbs near-infrared rays at wavelengths near 760 nanometers. Consequently when near-infrared rays are made incident on the palm of a hand, reflection is reduced only in the areas in which there are veins, and the intensity of the reflected near-infrared rays can be used to identify the positions of veins.
The user first uses an image capture device to register vein image data of the palm of his own hand on a card. Then, in order to perform individual authentication, the user employs an image capture device to cause the vein image data of his own hand to be read. The registered vein image recorded on the card, and retrieved using the ID of the user, is verified against the vein pattern of the vein image for verification thus read to perform individual authentication.
On the other hand, in the field of fingerprint authentication, a method of biometrics authentication of an authorized agent has been proposed in which fingerprint information for an authorized agent other than the principal is registered in advance, and by performing fingerprint authorization of the authorized agent, a single card can be used for biometrics authentication of an authorized agent (see for example Japanese Patent Laid-open No. 2001-067523) and Japanese Patent Laid-open No. 2001-202494). That is, the fingerprints of an authorized agent who has received the consent of the principal are registered, enabling biometrics authentication of the authorized agent. In this method of the prior art, at the time of card issue, the biometrics information of the principal and, with the consent of the principal, the biometrics information of the authorized agent are registered as authorization details.
For example, in Japanese Patent Laid-open No. 2001-067523, on a single card, the principal is registered so as to be able to perform all transactions (deposits, withdrawals, fund transfers from an ordinary deposit account, deposits, withdrawals, fund transfers from a savings deposit account, and similar), and an authorized agent (proxy) is registered so as to be able to perform a portion of these (for example, deposits and withdrawals to and from the ordinary account) in the use of ATM (automated transaction machine) that utilizes biometrics authentication for transaction processing. To this end, authorization details for the authorized agent can be stipulated, and a single card can be used by both the principal and the authorized agent, for greater convenience.
On the other hand, in actual features there is a need for the biometrics information of an authorized agent to be registered or deleted on a card on which the biometrics information of the principal has first been registered. Further, there is also a need for previously registered authorization details of an authorized agent to be modified. For example, there may be a need to change authorization details when there are changes in the employment situation or family composition of the authorized agent.
Using the technology of the prior art, however, it is difficult to register, modify, or delete the biometrics information of the authorized agent securely to satisfy this demand, and the security of the authorization method based on biometrics authentication is impeded. As a result, widespread adoption of such an authorization method is difficult.